Hi all,
I try to connect ARM microcontroller (LPC1768) to Huawei MC703 (CDMA EVDO), using Keil library RLARM 4.12.
Connect using PC, Windows XP dial up modem and Huawei MC703 EVB: - RTS/CTS line used, connection is made and data transfer is OK. - RTS/CTS line is not used, data transfer is not OK.
Connect using LPC1768, RL.ARM 412 (PPP and modem dial) and Huawei MC703 EVB: - Received "CONNECT" message, but no subsequent data can be sent, even if RTS/CTS line is used. - Same firmware is used to connect with SIM900 GSM, and no problem found, RTS/CTS is not used.
My questions is: - Does RTS/CTS line mandatory or make modem connection more reliable? I never use this control line before. - Are there any difference in compression code, activation, security etc between CDMA and GSM? - Please help to give suggestions what to do next (we have a plan to purchase Serial Analyzer to compare PC data and ARM data.)
Thank you for all members attention
Regards Ojahan